Abstract: The invention relates to a gluing apparatus which can be used in particular as part of a book casing-in machine. The gluing apparatus includes an application roller for applying a glue layer to a surface to be glued and a dosing roller for dosing the amount of glue. The application roller comprises an axis-parallel depression and the dosing roller comprises an axis-parallel projection engaging in the depression. The profile of the projection (20) of the dosing roller (2) merges from the cylindrical peripheral surface (4) via an involute into a coaxial cylindrical portion (22) of greater diameter while the profile of the depression (10) of the application roller (1) merges from the cylindrical peripheral surface (3) via a curve forming the counter profile to the involute of the projection (20) into a coaxial cylindrical portion (12) of smaller diameter.